Safety hydraulic brake structure



May 14, 1940. l J. F. GUDERIAN 2,201,085

SAFETY HYDRAULIC BRAKE .STRUCTURE Filed June 15, 1959 2 Sheets-Sheet 1 May 14, 1940. J. F. GUDERIAN 2,201,085

SAFETY HYDRULIC BRAKE STRUCTURE AFiled June l5. 1939 2 Sheets-Sheet 2 xml/hump named Maf 14, 194e I 2,201,0ait

SAFETY HYDRAULIC BRAKE s'rnUc'rUm:

Juel F. Guderian, Coquille, Orez., assigner o! oneiourth to James Richmond and one-fourth to Georgia G. Richmond, Coquille, Orcx.

Application June 15, 1939, serial No. 279,367

(ci. isa-152) 2 Claims.

This invention relates to an hydraulic brake provide means which will render operation oi such brakes safer and particularly in the case of leakage.

.The invention is particularly applicable to a system having a plurality of master cylinders, forinstance two or four, and it aims to provide meanswhereby through the travel of the pistons in the cylinders, communication between the cylinders will be cut oil, thus rendering each master cylinder and associated brake or brakes, inde- `stated in combination with means which will increase the piston travel within the brake cylinder or cylinders to accomplish the end stated,

`vstructure or mechanism and it aims generally toy tain the devices II and I6 unapplied, through the medium of expansive springs I8 in the cylinders. The outlet connections from the cylinders I to the pipes I2 and I4 .are shown at I9 and 20, respectively.

Mounted on the cylinders IU is a reservoir or supply tank 2i adapted to contain hydraulic fluid which may enter the cylindersand coopcrate with the pistons in the mual manner through ports 22, aided by relief ports 23. Pistons i1 vare shown as of the usual spool type, having a conventional packing cup as at 24 at one end thereof and a packing ring as at 25. Tanker reservoir 2i may be filled through an openingl normally closed by a screw plug at 26.

In accordance with the present invention, ports 2l are provided through the cylinder walls in the rear of the forward limit of movement of the Without increasing the speed necessary for operatin or depression of the brake pedal.

The more specinc objects and advantages will become apparent from a consideration of the description following taken in connection with the accompanying drawings illustrating an operative embodiment.

In said drawings- Figure l is a view in plan showing my improvements as used in a two master cylinder type' of hydraulic brake mechanism, the cylinder being shown in horizontal section to disclose details;

Figure 2 is a View primarily in side elevation, partly broken away, of the parts of Figure l,

Figure 3 is an end elevation showing the master cylinders;

Figure i is a central vertical longitudinal sectional view through one oi the master cylinders and Figure 5 is a plan view of a modified form, showing the invention applied to mechanism of the type having four master cylinders.

Referring specincally to the drawings and first to the form oflilaures l. to e, two master cylinders are provided at i@ which are usually in unitary or coupled relation as shown, one oi which communicates with and is associated with conventional hydraulic braise devices ii for iront wheels. of a vehicle, through the medium oi communicating conduits i2 and it. The other of such cylinders communicates, through conduits i4 and it, with conventional hydraulic brake devices it, similar to those atv i I.

Operating within the cylinders it are conlventlonal. pistons il, urged to retracted position,

as in vfull lines in the drawings. to normally mainpistons I1 and a tube or conduit means 28 is secured to both cylinders and establishescommunication between such cylinders.

Said pistons I'I have rods 29 extending exteriorly thereof which are slidably mounted in uuid-tight end closures 30 of the cylinders and joined by a crosshead 3i from which a push rod 32 extends normally into contact with a brake pedal lever pivoted as at 34. The pedal proper is shown 'at'lthe upper end of lever 33 as at di., Above rod 32, an auxiliary lever 36 ls pivoted at 3l to lever 33 and at 33 to the rod it. Such levertt is normally maintained in the position` shown in Figure 2 through the action of the springs it.

On a suitable part of the automobile or v hicle equipped witnmy improvements, a stop or abutment element d@ is mounted for contact by the upper end of the lever to. This stop 39 is shown as :provided with screw threads at 40 engaging a bracket di on the dashboard 42 of the vehicle, a lock nut t3 engaging the threads it and bracket di. l

Onmost cars, the brake pedal such as 33 has sin inches travel before it touches the loorboard, and such six inches travel imparts from one and one-quarter to one and one-half inches ofltravel to the master cylinder pistons il. This is given `by way of example, since the travel and operation will depend on the size of the master cylinders and other parts ci the hydraulic brake mechanism. when such pedal 33 is pushed for instance three and one-half inches toward the hooi-board, the pistons 'i will have just closed the brake equalizer and safety tube ports 21, thus cutting ofi ,communication between the master cylinders, and rendering them independentof each other, thus restricting possible leakage in one of them in case of impairment, and minimizing nuid losses and increasing safety, and

-enabling operation for a time sulcient to obtain` at the same speed as the lever 33, due to the contact of the rod 32 therewith, until the upper end of lever 36 abuts the stop 39, whereupon further movement of the lever 3 3 toward the oorboard, ,rocks lever 36 relatively to lever 33, on pivot 31, and moving rod 32 and the pistons I1 'away from lever 33 and at a greater speed, thus further increasing safety. It will be noted that although the speed of travel of the pistons is increased, it does not require an increase in the speed of operation of the foot pedal 33.

A modication is shown in Figure 5 wherein a unit 44 of four units or hydraulic cylinders and cooperating pistons is shown, each piston cooperating through a conduit 45 with a brake device or mechanism 46 at each of the four wheels of the vehicle. Associated with the cylindersis a supply tank for the hydraulic uid at 2 I ccmmunicating with each cylinder through the medium of ports like those at 22 and 23 and al1 of the cylinders having an equalizing tube or conduit 23 communicating with each cylinder, at the same relative location as the conduit 28 in the previous form, and coacting with the pistons in the cylinders in the same manner. All four pistons have rods 29 extending exteriorly of the cylinders and connected by a crosshead 3| which in turn through a rod 32', is adapted for oper- Iward position, like the dotted line position in Figure 4. Various changes may be resorted to provided they fall within the spirit and scope of the invention.

I claim as my invention:

1. In a iiuid operated brake system, cylinders, brake devices operable one from each cylinder,

means establishing communication between the cylinders, pistons operable in the cylinders, said means being disposed for closing through movement of one of the pistons to apply the brakes, a lever operable to apply the brakes, and means associated with said lever operable to move the pistons faster than the lever following initiation of movement of the lever.-

2. In a uid operated brake system, cylinders, brake devices `operable one from each cylinder, means establishing communication between the cylinders, pistons operable in the cylinders, said means being disposed for closing -through movement of one of the pistons to apply the brakes, a lever operable to apply the brakes, and means associated With said lever operable to move the pistons faster than the lever following initiation of movement of the lever, consisting of a lever pivoted to the first mentioned lever and'to the piston, and abutment means for engagement by the second mentioned lever on the opposite side of its fulcrum to the pistons.

JUEL F. GUDERIAN. 

